Here are some things that, when first encountering them during my formative years in high school and in college in the early seventies, I was sure I knew what they meant. Now, in the autumn of my years, I know that I had no idea then what these things mean, and I am beginning to think that just now I am getting the idea.
"It's amazing how much mature wisdom resembles being too tired."
~ Robert Heinlein, The Notebooks of Lazarus Long, 1975
~ Mary Hopkin, Those Were the Days, 1968
"Some parts wake up faster than others."
~ Sonny Steele (Robert Redford) in Electric Horseman, 1979
"Youth is wasted on the young."
~ Folklore and It's a Wonderful Life ("Youth is wasted on the wrong people!")
~ Frank Sinatra, When I was Seventeen, 1965
"I know one thing, that I know nothing."
~ attrib. Socrates